Publications

2011

• Modelling the settling of suspended sediments for concentrations close to the gelling concentration
  
  • Camenen B.
  • Pham van Bang Damien
  Continental Shelf Research, Elsevier, 2011, 31, pp.p. 106 - p. 111. This paper deals with the sedimentation of highly concentrated sediment suspensions (cohesive as well as non-cohesive) and the beginning of the consolidation of cohesive sediments. Based on a comparison of existing empirical formulas and experimental data, the particle Reynolds number was shown to be of importance for the behaviour of particularly non-cohesive sediments. In addition it plays a role in determining whether one or two interfaces develop during the sedimentation phase. In the case of cohesive sediments, the estimation of the gelling concentration, although difficult, seems to be fundamental. Some suggestions on the estimation of the permeability coefficient and total settling function are then given in order to improve the modelling of the sedimentation and consolidation behaviour for concentrations close to the gelling concentration. (10.1016/j.csr.2010.07.003)
  DOI : 10.1016/j.csr.2010.07.003
• Vertically averaged models for the free surface Euler system. Derivation and kinetic interpretation.
  
  • Sainte-Marie Jacques
  Mathematical Models and Methods in Applied Sciences, World Scientific Publishing, 2011, 21, pp.459-490. Starting from the Euler equations for incompressible flows, we propose an extension of the classical Saint-Venant system where the non-hydrostatic pressure terms are taken into account in the asymptotic expansion. We also derive a multilayer version of this vertically averaged Euler system. The multilayer approach allows mass exchanges between the neighboring layers. Finally we give a kinetic type interpretation for the proposed models. (10.1142/S0218202511005118)
  DOI : 10.1142/S0218202511005118
• Nonlinear fluid-structure interaction problem. Part I: implicit partitioned algorithm, nonlinear stability proof and validation examples
  
  • Kassiotis Christophe
  • Ibrahimbegovic Adnan
  • Niekamp Rainer
  • Matthies Hermann G.
  Computational Mechanics, Springer Verlag, 2011, 47, pp.305-323. In this work we consider the fluid-structure interaction in fully nonlinear setting, where different space discretization can be used. The model problem considers finite elements for structure and finite volume for fluid. The computations for such interaction problem are performed by implicit schemes, and the partitioned algorithm separating fluid from structural iterations. The formal proof is given to find the condition for convergence of this iterative procedure in the fully nonlinear setting. Several validation examples are shown to confirm the proposed convergence criteria of partitioned algorithm. The proposed strategy provides a very suitable basics for code-coupling implementation as discussed in Part II. (10.1007/s00466-010-0545-6)
  DOI : 10.1007/s00466-010-0545-6
• TELEMAC: An efficient hydrodynamics suite for massively parallel architectures
  
  • Moulinec Charles
  • Denis Christophe
  • Pham C.-T.
  • Rougé D.
  • Hervouët Jean-Michel
  • Razafindrakoto Emile
  • Barber R. W.
  • Emerson D. R.
  • Gu X. J.
  Computers and Fluids, Elsevier, 2011, 51 (1), pp.30-34. This paper investigates the use of TELEMAC (a Finite Element-based hydrodynamics suite) on massively parallel computer architectures. The performance of TELEMAC is illustrated using two separate test cases. The first considers the use of TELEMAC-2D for simulating tidal currents in the vicinity of a renewable energy marine turbine farm, in order to provide reliable estimates of the expected energy yield. The second demonstrates the use of TELEMAC-3D for assessing the effects of fresh water discharges on the salinity distribution in a coastal lagoon. The simulations have been performed with meshes ranging from 2 to 12 million elements, and good scaling performance is achieved on a variety of different computer architectures. (10.1016/j.compfluid.2011.07.003)
  DOI : 10.1016/j.compfluid.2011.07.003
• Multilayer Saint-Venant Equations over movable beds
  
  • Audusse Emmanuel
  • Benkhaldoun Fayssal
  • Sainte-Marie Jacques
  • Seaid M.
  Discrete and Continuous Dynamical Systems - Series B, American Institute of Mathematical Sciences, 2011, 15 (4), pp.917-934. We introduce a multilayer model to solve three-dimensional sediment transport by wind-driven shallow water flows. The proposed multilayer model avoids the expensive Navier-Stokes equations and captures stratified horizontal flow velocities. Forcing terms are included in the system to model momentum exchanges between the considered layers. The topography frictions are included in the bottom layer and the wind shear stresses are acting on the top layer. To model the bedload transport we consider an Exner equation for morphological evolution accounting for the velocity field on the bottom layer. The coupled equations form a system of conservation laws with source terms. As a numerical solver, we apply a kinetic scheme using the finite volume discretization. Preliminary numerical results are presented to demonstrate the performance of the proposed multilayer model and to confirm its capability to provide efficient simulations for sediment transport by wind-driven shallow water flows. Comparison between results obtained using the multilayer model and those obtained using the single-layer model are also presented. (10.3934/dcdsb.2011.15.917)
  DOI : 10.3934/dcdsb.2011.15.917